Cellulose is a sustainable, renewable, environmentally-friendly, and biodegradable biopolymer that can be obtained from biomass and abundant resources. Cellulose has interesting properties and lends itself to modification; it has many derivatives and many modified forms. For many years, cellulosic polymers have been employed in the pharmaceutical industry.
Tablets are a major pharmaceutical dosage form. They are characterized by their hardness and ability for drug delivery. Tablets must be hard enough to tolerate any mechanical forces during packaging and transportation. At the same time, tablets hardness should be optimized to suit various drug delivery systems. Tablets are currently prepared by solid-state mixing of active ingredients with excipients such as starch, gelatin, and sugars. Wet or dry granulation is then performed to prepare the mixture for tablet compression using a punch machine [Edward M Rudnic, J. B. S., Oral Solid Dosage Forms. Remington: the science and practice of pharmacy. 21st ed. Philadelphia, Pa.: Lippincott Williams & Wilkins, 2005: p. 8921]. This technology is typically implemented by batch processing. Batch processing has many disadvantages including the variety of required equipments [Leuenberger, H., New trends in the production of pharmaceutical granules: batch versus continuous processing. European journal of pharmaceutics and biopharmaceutics, 2001. 52(3): p. 289-296] and batch-to-batch differences [E. M. Redunic, supra].
Continuous processing is promising technology that is used mainly in the food industry. Continuous processing is expected to be more economical and uses less equipment, labor and energy [A. Pellek, P. V. A., Continuous Processing: Moving with or against the manufacturing flow. Pharmaceutical Technology, 2008: p. 52-583]. Accordingly, there is a need for new ways to produce pharmaceutical tablets that are adaptable to continuous processing techniques.